The looming threat of Lionel Messi was the main topic of conversation outside the Etihad Stadium before Manchester City's first taste of Champions League knock-out football. "They've got Messi but we've got David Silva and he's just as good," a City supporter claimed on the giant television screen above. They say it is the hope that kills you. For City, it was the magician from Rosario, Argentina.

Messi did not deliver a vintage European display against Manuel Pellegrini's determined City side and the contributions of Andrés Iniesta, Dani Alves and Xavi reminded all that Barcelona's golden years were not built by one man. And yet, Messi ended the night on 66 goals from 83 Champions League appearances, five short of Raúl's record, having been instrumental in turning the tie away from City's reach and validating the Spanish champions' belief.

With an intelligent run behind the home defence and burst on to Iniesta's pass he tempted Martín Demichelis into the foul that left City with 10 men for 40 minutes and a Camp Nou mountain to climb in the second leg. The Etihad and Pellegrini may have raged at the performance of the Swedish referee, Jonas Eriksson, but it was Messi's decision-making that proved decisive. The outcome will fuel Gerado Martino's optimism of mounting a greater challenge to Bayern Munich.

Gerard Piqué's verdict that Barcelona's rivals "maybe don't fear us as before" was based on two successive Champions League semi-final exits having lifted the trophy at Manchester United's expense in 2009 and 2011. It is also no coincidence the perception of one of the finest teams of all time has shifted during what, by Messi's standards, has been a disquieting campaign on and off the pitch for the Argentina international.

Rare controversy has attached itself to the usually unblemished striker in the form of a court appearance over alleged tax fraud and an unprecedented row with a Barcelona director. Messi and his father, Jorge Horacio, made a €5m correction payment in the tax case. The 26-year-old also accused Javier Faus of being "someone who doesn't know anything about football" after the board member unwisely dismissed the genius' qualification for a pay rise. Wisely Faus has since taken steps to repair their relationship.

That Messi should break the habit of his Barcelona lifetime and publicly condemn a director of the club generated a sense of crisis around the Spanish champions before Christmas. More disconcerting for his club, country and the game itself with a World Cup on the horizon were the succession of injury problems that prompted allegations of burn-out in the four-time Ballon d'Or winner.

Barcelona's success and Messi's commercial appeal do not allow for an extended break from football and several hamstring problems, the last sidelining their No10 for two months, were as widely predicted as they were feared. It is remarkable, therefore, that the records have continued to crumble before Messi's astonishing left foot, even as he works his way back to full fitness.

Saturday's two goals against Rayo Vallecano brought Messi level with the Real Madrid legend Raúl as the third highest goalscorer in La Liga history, his 228 league goals arriving in 263 games. To put that into an historical context, it took Alfredo Di Stéfano 359 matches to score 227 league goals in Spain. Telmo Zarra (251 goals) and Hugo Sánchez (234) are unlikely to remain in first and second place for too long.

Injuries have not slowed the striker's phenomenal goalscoring rate this season with 13 goals in 17 league appearances so far and six in only three Champions League outings. As he rediscovers fitness and form, the lustre surrounding Barcelona and their prospects of winning a fifth European Cup also return. They need everyone at their peak to prevent their former coach Pep Guardiola overseeing another era of dominance, only this time in Germany.

Messi was a slow-burning fuse at the Etihad. Pellegrini claimed "we will not plan for individual opposition players" in his programme notes but his team's reaction whenever the Argentinian took possession suggested otherwise. It was credit to the work-rate, awareness and defensive discipline of Yaya Touré and the fit-again Fernandinho that Messi received the ball in a position to turn and run at City's back-line only three times in the first half.

On each occasion he was smothered away from danger with Vincent Kompany quickly alert to any danger, Fernandinho a constant shadow and Demichelis an astute presence in his favoured central defensive position before the turning point.

City's initial success in stifling the supply to Messi was reflected by how his most eye-catching contribution came before the game kicked off. His warm-up routine with Alves was worth the price of admission alone, as Alves pumped a series of 40-yard balls high into the air and Messi controlled each one perfectly with a different part of his anatomy before volleying the ball back to the Brazilian. But he cannot be stifled forever.

One sublime pass from Iniesta and one lapse in concentration in the heart of the City defence was all it took for Messi to leave an indelible mark on the tie. He looked more vibrant from the start of the second half and seized on Iniesta's through-ball only to be clipped as he entered the area by Demichelis. As his unfortunate compatriot trudged off the field with a red card, Messi picked himself up to stroke the penalty down the centre of Joe Hart's goal and spark wild celebrations of his first goal in nine appearances at a Premier League stadium. One moment. All he needs.

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